Perfluoroalkyl compounds,their manufacture,their polymerisation products and their use

ABSTRACT

PERFLUOROALKYL COMPOUNDS ARE PROVIDED IN WHICH THE PERFLUOROALKYL RADICAL IS BOUNDED THROUGH A LINEAR OR CYCLIC ALIPHATIC RADICAL TO THE CARBOXYLIC GROUP OF AN ALIPHATIC UNSATURATED CARBOXYLIC ACID. THESE PRODUCTS AND THEIR POLYMERIZATION PRODUCTS ARE USEFUL FOR FINISHING VARIOUS SUBSTRATES, ESPECIALLY FOR THE PRODUCTION OF ALIPHATIC FINISHES ON THE PAPER, LEATHER, NON-WOVENS AND TEXTILES.

3 836 577 PERFLUOROALKYL C OM POUNDS, THEIR MANU- FACTURE, THEIR POLYMERISATION PROD- UCTS AND THEIR USE Horst Jaeger, Wyhlenweg 10, Bettingen, Switzerland, and

Paul Schaefer, Morystrasse 88, Riehen, Switzerland N Drawing. Original application Aug. 17, 1971, Ser. No. 172,545, now Patent No. 3,780,093. Divided and this application May 16, 1973, Ser. No. 360,873 Claims priority, application Switzerland, Aug. 24, 1970, 12,591/70 Int. Cl. C07c 69/54 US. Cl. 260-486 H 2 Claims ABSTRACT OF THE DISCLOSURE Perfluoroalkyl compounds are provided in which the perfluoroalkyl radical is bounded through a linear or cyclic aliphatic radical to the carboxylic group of an aliphatic unsaturated carboxylic acid. These products and their polymerization products are useful for finishing various substrates, especially for the production of aliphatic finishes on the paper, leather, non-Wovens and textiles.

This application is a divisional of copending application Ser. No. 172,545, filed on Aug. 17, 1971, now US. Pat. 3,780,093.

The subject of the invention are perfluoroalkyl compounds of the formula wherein R and R each denote a perfluoroalkyl radical with 6 to 24 carbon atoms, A and A each denote a radical of the formula and, where n=1, each denote an acyclic alkylene radical with up to 12 carbon atoms which is bonded to R and R by the carbon atom (1), E denotes an alkenylene radical with 2 tor 3 carbon atoms, and m and n each denote 1 or 2.

The acyclic alkylene radical for example corresponds to the formula R and preferably CH1CH or -CH;CH1C CH;GH-

H3 H; CH3 l. l.

wherein R, and R denote a hydrogen atom or an alkyl radical with 1 to 4 carbon atoms.

Here, perfluoroalkyl compounds of the formula wherein R and R each denote a perfluoroalkyl radical with 6 to 18 carbon atoms and A, A, E and n have the indicated meaning, are of particular interest.

United States Patent 0 3,836,577 Patented Sept. 17, 1974 Amongst these perfluoroalkyl compounds, those of the formula wherein p is 1 or 2 and R, R, A, A and n have the indi-- cated meaning.

The alkylene radical E or the radical of the formula C H are radicals which are, for example, derived from acrylic, methacrylic, crotonic, vinylacetic, maleic, fumaric, itaconic or citraconic acid, that is to say, for example, radicals of the formula Accordingly, very suitable perfluoroalkyl compounds correspond to the formula wherein E represents a radical of the formula (5.1), (5.2) or (5.3) and R, R, A, A' and n have the indicated meaning.

Depending on whether n is l or 2, the compounds of the formulae (1) to (4) and (6) are dicarboxylic acid esters or monocarboxylic acid esters or diperfluoroalkyl compounds or monoperfluoroalkyl compounds.

In the formulae (1) to (4) and (6), n is preferably 2. Preferred compounds of this nature correspond to the formula wherein q denotes an integer from 5 to 13 and X denotes hydrogen or methyl, the ester radical in the formula (7) being in the 4- or 5- position of the 6-membered ring.

Suitable perfluoroalkyl compounds correspond to the formula wherein q is an integer from to 13 and the ester radical is in the 4- or 5-position of the G-membered rings.

Particularly interesting perfluoroalkyl compounds correspond to the formulae (4) C B Z) q (4) CF1(CF:) I

(3) onion 1 (3) C dG t hV z Fa( F:)u-

2 isomeric testers (3) onion is reacted with a carboxylic acid of the formula KOH or an anhydride, acid halide or lower alkyl ester thereof, R, A, E and n having the indicatedmeaning and r being Preferably, this reaction is carried out in the presence of an organic solvent and optionally in the presence of an acid catalyst.

The preferred temperature for this reaction is 20 to 150 C.

Starting products of the formula (14) for this reaction are, for example, acrylic, methacrylic, crotonic, maleic,

4 fumaric or itaconic acid. Starting products of the formula (13) correspond, for example, to the formula 15. 1 Fa z)q q=5 to 13 or FSG (CFI)Q or its isomers.

A second process for the manufacture of perfiuoroalkyl compounds of the formula (1), wherein A or A each represent a radical of the formula (1.1), (1.2) or (1.4) and m is 1 or 2 is characterised in that hydrogen iodide is split off, in the presence of a base, from a compound of the formula wherein G and G each represent a radical of the formula and m, n, R, R, and B have the indicated meaning.

This process, again, is preferably carried out in the presence of an organic solvent.

The most advantageous temperature for this elimination of hydrogen iodide is 20 to 150 C.

The saturated starting substances for the first process are obtained by a hydrogenating deiodination.

This deiodination with nascent hydrogen takes place in accordance with the equation.

, Metal CF3 CFfl Ta-'9 CF3(CF2)3 Cl 0]. onion alcohol 0111011 Possible acids are inorganic acids such as hydrochloric or sulphuric acid, or organic acids such as acetic acid. Methanol or ethanol is preferably used as the alcohol.

The alcohols thus obtained can be esterified to give compounds of the formula (1 The elimination of the iodine can also be effected by catalytic hydrogenation, in which case Raney nickel, platinum or palladium may be mentioned as catalysts. This elimination is appropriately carried out in-the presence of an organic acid, such as acetic acid, or of an alkanol, such as ethanol.

The organic solvents preferentially used for those two processes are solvents which are inert, that is to say do not participate in the reaction, such as, for example: benzene, toluene and ethyl acetate for the esterification reaction. Alkanols such as methanol, ethanol or propanol are used for the elimination of hydrogen iodide.

In the case of the elimination by hydrogen iodide by means of organic bases such as triethylamine, the base itself can serve as the solvent.

Perfluoroalkyl compounds of the type of the compounds of the formula (12) are manufactured by esterification of the corresponding 2-perfiuoroalkyl-isopropanol (obtained from the corresponding iodide) with a carboxylic acid of the formula (14), in accordance with customary methods.

As a result of their alkenyl group the perfluoroalkyl compounds of the formula (1) can be homopolymerised, or copolymerised with other ethylenically unsaturated copolymerisable compounds.

The polymerisation of the monomeric perfiuoroalkyl compounds can be carried out in solution or in emulsion and in the presence of catalysts which release free radicals or act by an ionic mechanism, the compounds being polymerised with themselves, with other perfluoroalkyl compounds according to the invention or with other polymerisable compounds to give linear polymers.

The following are suitable for copolymerisation with the perfluoroalkylmonocarboxylic acid esters:

(a) Vinyl esters of organic carboxylic acids, for example vinyl acetate, vinyl formate, vinyl butyrate and vinyl benzoate,

(b) vinyl alkyl ketones and vinyl alkyl ethers such as vinyl methyl ketone and vinyl butyl ether,

(c) vinyl halides, such as vinyl chloride, vinyl fluoride and vinylidene chloride,

(d) vinylaryl compounds, such as styrene and substituted styrenes,

(e) derivatives of the acrylic acid series, such as acrylonitrile or acrylamide and preferably its derivatives which are substituted at the amide nitrogen, such as N-methylolacrylamide, N-methylolacrylamide-alkyl ether, N,N-dihydroxyethylacrylamide, N-tert.-butylacrylamide and triacrylyl-hexahydrotriazine,

(f) esters of the acrylic acid series, such as esters of acrylic acid, methacrylic acid, a-chloroacrylic acid, crotonic acid, maleic acid, fumaric acid or itaconic acid and monoalcohols or dialcohols with l to 18 carbon atoms or phenols, for example ethyl acrylate, glycidyl acrylate, butyl acrylate, acrylic acid monoglycol ester of dodecyl acrylate, and

/ (g) polymerisable olefins such as isobutylene, butadiene or 2-chlorobutadiene.

Preferably, the following are used: esters, amides or methylolamides of acrylic acid or methacrylic acid, such as acrylic acid ethyl ester, acrylic acid butyl ester, acrylic acid glycidyl ester, glycol monoacrylate or calcium acrylate, acrylamide, methyl methacrylate, methyl acrylate, acrylarnide, methacrylamide, N-rnethylolacrylamide, N methylolacrylamide-methyl ether and N-tert.-butylacrylamide; vinyl esters of organic carboxylic acids such as vinyl acetate; styrene, vinyl halides such as vinyl chloride or vinylidene chloride, or polymerisable olefines such as isobutylene.

The polymers as a rule consist of 5 to 100 percent by weight of a perfluoroalkyl compound and of 95 to percent by weight of a different compound. Polymers which contain to 30, preferably 8 to 20, percent by weight of copolymerised monomeric perfiuoroalkyl compound, relative to the total weight of the monomer units, possess particularly interesting technical properties. Amongst these polymers, in turn, the binary or ternary copolymers which in addition to 5 to 30 percent by weight of the perfluoroalkyl compound also contain a copolymerised acrylic acid ester, such as butylacrylate and option ally a copolymerised third monomer, especially a vinvl ester, such as vinyl acetate, are in turn distinguished by particularly advantageous technical properties, especially in the field of textile finishing.

The manufacture of the polymers by homopolymerisation of the perfiuoroalkyl compounds with one or more other copolymerisable ethylenically unsaturated monomers is carried out according to customary methods, for example by block polymerisation, bead polymerisation, graft polymerisation or polymerisation in aqueous emulsion, or preferably by solvent polymerisation in an organic solvent suitable for this purpose, such as, for example,

acetone, benzene, sym.-dichloroethane or ethyl acetate.

The polymerisation is appropriately carrier out with warming, preferably to the boiling point of the solvent, and with addition of ionic catalysts or of peroxide or other catalysts which form free radicals and which are soluble in the reaction medium such as, for example, benzoyl peroxide, lauroyl peroxide, or a,a-azoisobutyrodinitrile.

Depending on the nature of the polymerisation conditions and on the monomeric starting substances used, the polymeric compounds are obtained in the form of viscous solutions, of granules or of emulsions.

It is furthermore also possible to carry out the polymerisation of the monomeric compounds in the presence of substrates. It can, for example, be effected on glassfibre fabric or textile material. In this case, a suitable method is to impregnate the substrate in question with solutions or emulsions of the monomers and subsequently to carry out the polymerisation by heating the material, a polymerisation catalyst being added.

The monomeric perfluoroalkyl compounds and their polymers are advantageously used together with compounds which contain several reactive functional groups, such as 1,2-ep0xy groups, isocyanate groups, acrylyl groups, methylol groups, methylol groups etherified with lower alcohols, aldehyde groups, easily hydrolysable ester groups and the like. Such polyfunctional compounds are also suitable for use as crosslinking components, or curing or fixing components, for the copolymers according to the invention where these contain, for example, free hydroxyl groups.

As such components there may in particular be mentioned: epoxide compounds, namely polyglycidyl ethers, such as butanediol diglycidyl ether and diglycidyl ether, diisocyanates and polyisocyanates, such as o-, mand pphenylenediisocyanate, toluylene-2,4-diisocyanate and 1,5- naphthylenediisocyanate; acrylyl compounds such as methylene-bis-acrylamide and symmetrical triacrylylperhydrotriazine; poly (2,3-dihydro-1,4-pyranyl) compounds, such as (2,3-dihydro-1',4-pyran-2-yl)-methyl ester; alhehydes, such as formaldehyde or glyoxal, and soluble phenol-formaldehyde condensation products such as novolacs or resols. Preferably, aminoplasts which are soluble in water or in organic solvents are used as crosslinking components. Possible aminoplasts are formaldehyde condensation products of urea, thiourea, guanidine, acetylenediurea and dicyandiamide, and also of aminotriazines, such as melamine or of guanamines, such as acetoguanamine, beuzoguanamine, tetrahydrobenzoguanamine or formoguanamine as well as their ethers with alcohols, such as methyl alcohol, ethyl alcohol, propyl alcohol, allyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol. cyclohexanol, benzyl alcohol, lauryl alcohol, stearyl alcohol, oleyl alcohol or abietyl alcohol. In addition to the ether radicals, the condensation products can also contain radicals of higher-molecular acids, such as, for example stearic acid.

Particularly good technical results in the field of textile finishing are obtained on using water-soluble condensation products of formaldehyde and melamine or especially on using the esterification or etherification product of hexamethylolmelamine-methyl ether and stearic acid or stearyl alcohol, as crosslinking or fixing components.

The homopolymers and copolymers of the perfiuoroalkyl compounds can also be used mixed with polymers not containing fluorine. Very suitable polymers not com taining fluorine are here, for example, the homopolymers of acrylic acid esters or methacrylic acid esters, such as poly(ethyl acrylate) or copolymers of acrylic acid esters or methacrylic acid esters with methylolacrylamide or methylolmethacrylamide.

The perfluoroalkyl compounds of the formula (1) can be used, either as such or as homopolymers or copolymers, for the finishing of porous substrates, preferably for the production of oleophobic finishes thereof. Paper, leather,

non-Wovens or, especially, fibre materials such as textiles may be mentioned as porous substrates.

To render them oleophobic, the substrates can be treated either with solutions or with dispersions or emulsions of the monomeric or polymeric perfluoro compounds. The monomers can, for example, be applied to the textile material from a solution with an organic solvent and can be thermally fixed to the fabric after evaporation of the solvent. Polymers can also be applied to the fabric from suitable solvents.

Possible textile materials which can preferably be treated with the monomeric or polymeric per'fluoro compounds are, for example, those of native or regenerated cellulose, such as cotton, linen or rayon, staple viscose or cellulose acetate. However, textiles of wool, synthetic polyarnides, polyesters or polyacrylonitrile can also be used. Mixed woven fabrics or mixed knitted fabrics of cotton-polyester fibres can also be finished advantageously. In these cases the textiles can be in the form of filaments, fibres or flocks, but preferably in the form of woven fabrics or knitted fabrics.

Preparations which contain the monomeric or polymeric perfluoro compounds can be applied to the substrate in the usual manner which is in itself known. Woven fabrics can for example be impregnated by the exhaustion process or on a padder which is charged with the preparation at room temperature. The impregnated material is thereafter dried, preferably at 60 to 120 C., and subsequently optionally still subjected to a heat treatment at above 100 C., for example at 120 to 200 C.

Preparations which in addition to the monomeric or polymeric perfluoroalkyl compounds also contain components with properties imparting a hydrophobic character, for example solutions or emulsions of fatty acid condensation products, for example with aminoplast precondensates or paraffin emulsions, produce an oilrepellent effect, coupled with a water-repellent efiect, on the substrates treated therevsu'th.

Furthermore, a so-called soil release and antisoiling effect can also be achieved with the perfluoroalkyl compounds, especially the polymers, above all on cotton.

Example 1 26.4 g. of a compound of the formula FaC-(C F2);

I -CHzOH are treated, in a 200 ml. round flask, with 100 ml. of 50% strength potassium hydroxide solution and subjected to a steam distillation. 13.2 g. of a clear, colourless substance are obtained, which after distillation has a boiling point of 45 to 100 C. at 12 mm. Hg. The following compound is identified by recording a mass spectrum FaC(CF2)q q k CHzOH 13 g. of the alcohol of the formula (102) are dissolved in 100 m1. of absolute benzene. 2.2 g. of methacrylic acid, 0.5 g. of p-toluenesulphonic acid and 0.2 g. of hydroquinone-monomethyl ether are weighed out into this solution.

This reaction mixture is heated to 82 C. reflux temperature. After 3 hours reaction time, no further separa tion of water is observable. The methacrylic acid ester is cooled to room temperature and the benzene solution is washed 3 times with 50 ml. of sodium bicarbonate solution until neutral, rinsed twice with 20 ml. of water, dried with sodium sulphate and concentrated in vacuo at 30 C.

Yield: 13.7 g.=89.3% of theory of a liquid compound.

The structure is confirmed by recording a mass spectrum:

0 CH3 smo -(kerb Example 2 37 g. of an epoxide of the formula OHsC CF (CF2) CH- CHHC are dissolved in 50 ml. of ethyl acetate. 1 g. of sodium acetate and 0.2 g. of hydroquinone-monomethyl ether was weighed out into this solution and the mixture is heated to the reflux temperature (75 C.). 4 g. of acrylic acid dissolved in 20 ml. of ethyl acetate are added dropwise at the reflux temperature and the mixture is allowed to react for 5 hours. The ethyl acetate is then removed in vacuo at 30 C., the residue is taken up in 200 ml. of diethyl ether and the solution is washed 3 times with 20 ml. of water, the neutral ethereal solution is dried with sodium sulphate and the ether is removed in vacuo.

Yield: 36.5 g. =89.6% of theory, of a pale yellowish,

viscous liquid.

The structure is confirmed by recording a mass spectrum.

22 g. of the compound of the formula (105) are dissolved in 50 ml. of triethylamine and stabilised with 0.5 g. of hydroquinone-monornethyl ether.

This mixture is kept for 3 hours at the reflux temperature at 55 C. The excess triethylamine is then distilled off under normal pressure and the residual amount of triethylamine is subsequently removed in vacuo. The residue is taken up in ml. of diethyl ether, washed with 3 times 20 ml. of water until neutral and dried with sodium sulphate, and the ether is distilled off. The residue is a highly viscous, light brown substance.

Yield: 15.5 g.=83.7% of theory.

The structure is confirmed after recording a mass spectrum CHr-O CH-CH=CH(CF2)u OF CH o 41: 5.9

In contrast to the spectrum of the substance of the for mula (104), no iodine is detected by mass spectroscopy in this case.

Example 3 (a) 30 g. of the perfluoroalkylisopropyl alcohol of the formula are dissolved in 200 ml. of (anhydrous) benzotrifiuoride. 0.05 g. of methoxyhydroquinone and 4.8 g. of fumaric acid dichloride are added to this solution.

The reaction solution is heated to the reflux temperature (102 0.). A vigorous evolution of hydrogen chloride gas commences. After 18 hours the reaction is completed. To work up the reaction mixture, the solution is diluted with 200 ml. of diethyl ether, washed 3 times with 100 ml. at a time of a sodium bicarbonate solution and twice with water and subsequently dried over sodium sulphate. The solvent is then removed in vacuo.

Yield: 29.9 g.:=60.5% of theory of a solid green-brown substance.

The mass spectrum confirms the following structure of the reaction product:

6 n=5, 7, 9 (b) If the fumaric acid dichloride is replaced by the corresponding dichloride of itaconic acid, a mixture of the symmetrical diester and the asymmetrical monoester is obtained, as was confirmed by the mass spectrum:

(108) ("I) -C [C F3(C F2)nCHz(|JHO-] +Hg CH1: 2 (i=CH2 II 0 n=5, 7, 9

109) 0M0 F2),.oH2oH-0-o- 3-oHz0ooH CH3 CH2 fl=5, 7, 9 30 g. of the compound of the formula OH OH are dissolved in 200 ml. of benzene. 0.5 g. of hydroquinone-monomethyl ether and 3 ml. of concentrated sulfuric acid are added to this solution and the mixture is heated to the reflux temperature (80 C.) 4.5 g. of acrylic acid dissolved in 10 ml. of benzene are then added dropwise and the mixture reacts for 6 hours. The benzene is then removed in vacuo at 30 C., the residue is taken up in 200 ml. of diehtyl ether and the solution is washed 3 times with 20 ml. of water. The neutral etheral solution is dried with sodium sulphate and the ether is removed in vacuo.

Yield: 16.7 g. (50.5% of theory) of the ester of the formula The structure is confirmed by recording a mass spectra.

Example According to the process of example 4 the following starting materials are reacted:

64.0 g. of the compound (110) dissolved in 300 ml. of

benzene 0.5 g. of hydroquinone-monomethylether 3 ml. of concentrated sulfuric acid 10.35 g. of methacrylic acid Yield: 46.1 g. (64% of theory) of the ester of the formula Ha g=5, 7, 9

The structure is confirmed by recording a mass spectra.

Example 6 Half of a mixture of 68 g. of water, 0.32 g. of sodium laurylsulphonate, 14 g. of acetone, 0.8 g. of acrylamide and 19.2 g. of the compound of the formula (103) is treated with 0.8 g. of 35% strength hydrogen peroxide, a solution of 0.4 g. of ascorbic acid in 6.5 g. of water and 0.4 g. of an 0.1% strength aqueous solution of ferrous ammonium sulphate at 20 0, Whilst stirring and passing nitrogen over the mixture. Thereafter the second half of the mixture is mixed with 0.8 g. of 35% strength hydrogen peroxide and introduced into the polymerisation vessel over the course of 30 minutes. A- solution of 0.4 g. of ascorbic acid in 6.5 g. of water is simultaneously but separately added dropwise. 20 minutes later 1.2 g., and minutes thereafter 2.4 g., of an 0.1% strength aqueous solution of ferrous ammonium sulphate are added. The mixture is allowed to complete polymerisation for 24 hours at room temperature, and about 120 g. of a finely disperse 16% strength emulsion, which leaves a clear, colourless film, are obtained.

Example 7 (a) A solution of 0.3 g. of azodiisobutyronitrile in 3 g. of acetone is added to a solution of 28.8 g. of the compound of the formula 103) and 1.2 g. of N-methylolmethacrylamide-methyl ether in 45 g. of acetone. The reaction mixture is warmed to 58 C. under a nitrogen atmosphere, Whilst stirring. -At intervals of 2 hours, solutions of 0.3 g. of azodiisobutyronitrile in 3 g. of acetone are added three times. After 30 hours reaction time, the solvent is distilled off the partially precipitated polymer. The residue is taken up in trifluoromethylbenzene and a 50% strength solution is produced.

(b) Instead of the compound of the formula (103 the compound of the formula (106) can also be employed in the polymerisation reaction described. A copolymer which is soluble in acetone, forms a clear smooth film, and can be applied from acetone solution, is obtained.

Example 8 A solution of 12 g. of the compound of the formula (107.2), 1.35 g. of vinyl acetate and 1.65 g. of styrene in 11 g. of trifiuorornethylbenzene is warmed to 50 C. under a nitrogen atmosphere, whilst stirring. 0.2 g. of lauroyl peroxide in 3 g. of trifluoromethylbenzene is added to this reaction mixture. After 2 hours the temperature is raised to 60 C. Solutions of 0.2 g. of lauroyl peroxide in 3 g. of trifluoromethyl-benzene are twice added, at intervals of 3 hours. After about 10 hours, the polymerisation is complete. A clear solution of a film-forming copolymer is obtained.

Example 9 The 16% strength emulsion from Example 3 is diluted with water to 4% solids content. Cotton poplin strips are dipped into this emulsion, squeezed out and dried for 5 minutes at C. in a drying cabinet in vacuo.

The oil-repellent effect is assessed according to the so-called 3 M oil repellency test (Crajeck and Petersen, Textile Research Journal 32, 320-331 1960)) in heptane- Nujol mixtures. In the assessment, is the best achievable rating. The individual samples are assessed immediately after drying, that is to say as obtained, and after an SNV-4 wash (=machine Wash for 30 minutes at 95 C., using a liquor ratio of 1:50, in a bath which contains 5 g. of soap and 2 g. of calcined sodium carbonate and a total of 10 steel balls per litre). The results are as follows:

Cotton Rating As obtained 120 After 1 x SNV-4 90 to 100 Example 10 1 1 1 2 The table wl:u'ch follows contains the composition of 2. A perfluoroalkyl compound according to claim 1 the preparations used and the results of the assessment wherein R is a perfluoroalkyl radical of 6 to 14 carbon of the oil-repellent effect. atoms.

Preparation fi'om Example 1 2 3a 3a 3b 5a 5b 6 Aceton 1,000 1,000 1,000 Efhannl 1, 000 1, 000 1, 000 Benzotrifiunrifle 1, 000 Concentration of the preparation (g./1.) 1O 4 8 8 30 Oilrepellent effect:

As obtained 100 120 110 110 100 100 so 100 IXSNV 4 90 70 100 1X dry cleaning 100 100 I claim: References Cited 1. A perfluoroalkyl compound of the formula 15 UNITED STATES PATENTS -E$= 3,660,360 5/1972 Chandhuri et a1. 260-486 H X 3,607,909 9/ 19711 Beregi et a1. 260-4-86 H wherein R is a perfiuoroalkyl radical of 6 to 24 carbon atoms, LORRAINE A. WEINBERGER, Primary Examiner 20 P. J. KILLOS, Assistant Examiner A is or -CH OH2 and X is hydrogen or methyl. 25

UNITED STATES PATENT AND TRADEMARK OFFICE CERTEHQATE OF CORRECTION PATENT NO. 3 836,577 DATED September 17, 197

lNV ENTOR(S) 1 HORST JAEGER ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 7, insert Assignee: CIBA-GEIGY AG,

Basle, Switzerland Signed and Scaled this eighth Day 0; June 1W6 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer I Commissioner uj'larems and Trademarks 

